arithmetic and logic unit

ALU, component of the central processing unit that performs calculations and logical operations

In computing, an arithmetic logic unit (ALU) is a digital circuit that performs arithmetic and logical operations. The ALU is a fundamental building block of the central processing unit of a computer, and even the simplest microprocessors contain one for purposes such as maintaining timers. The processors found inside modern CPUs and GPUs have inside them very powerful and very complex ALUs; a single component may contain a number of ALUs.
See more at Wikipedia.org...

A part of a computer that performs arithmetic, logic, and related operations.

<processor> (ALU or "mill") The part of the central processing unit which performs operations such as addition, subtraction and multiplication of integers and bit-wise AND, OR, NOT, XOR and other Boolean operations. The CPU's instruction decode logic determines which particular operation the ALU should perform, the source of the operands and the destination of the result.
The width in bits of the words which the ALU handles is usually the same as that quoted for the processor as a whole whereas its external busses may be narrower. Floating-point operations are usually done by a separate "floating-point unit". Some processors use the ALU for address calculations (e.g. incrementing the program counter), others have separate logic for this.
(1995-03-24)